Move subvolume handling to individual functions

This allows us to support different storage backends/filesystems
in the future.

diff --git a/bin/backup-script b/bin/backup-script
index 8d5e25e45e8dfc65427c907a4a355894881d41f8..60146d23f5a3d509a8b8ba0aaeb83a626b3a4f61 100755 (executable)
--- a/bin/backup-script
+++ b/bin/backup-script
@@ -95,6 +95,32 @@ ExecJob() {
        return $ret
 }
 
+CreateSubvolume() {
+       volume="$2"
+
+       btrfs subvolume create "$volume"
+}
+
+CloneSubvolume() {
+       source="$1"
+       volume="$2"
+
+       btrfs subvolume snapshot "$source" "$volume"
+}
+
+RenameSubvolume() {
+       source="$1"
+       target="$2"
+
+       mv "$source" "$target"
+}
+
+DeleteSubvolume() {
+       volume="$1"
+
+       btrfs subvolume delete "$volume"
+}
+
 while [ $# -gt 0 ]; do
        case "$1" in
          "-n"|"--dry-run")
@@ -256,7 +282,7 @@ for f in $sys; do
                if [ -n "$last" -a ! -e "$last/.stamp" ]; then
                        # Old backup directory without "stamp file", continue
                        echo "Found incomplete snapshot in \"$last\", reusing and renaming it ..."
-                       mv "$last" "$sys_target" >/dev/null 2>&1
+                       RenameSubvolume "$last" "$sys_target" >/dev/null 2>&1
                        if [ $? -ne 0 ]; then
                                echo "Failed to rename last snapshot \"$last\" to \"$sys_target\"!? \"$system\" skipped!"
                                echo; continue
@@ -265,10 +291,10 @@ for f in $sys; do
                        # Old backup directory found, create new snapshot
                        echo "Found last snapshot in \"$last\"."
                        if [ "$DRYRUN" -eq 0 ]; then
-                               btrfs subvolume snapshot \
+                               CloneSubvolume \
                                  "$last" "$sys_target" >/dev/null 2>&1; r=$?
                                if [ $r -ne 0 ]; then
-                                       echo "Can't create btrfs snapshot \"$sys_target\" of \"$last\", code $r!? \"$system\" skipped!"
+                                       echo "Can't create snapshot \"$sys_target\" of \"$last\", code $r!? \"$system\" skipped!"
                                        echo; continue
                                fi
                                echo "Created new snapshot in \"$sys_target\"."
@@ -278,10 +304,10 @@ for f in $sys; do
                else
                        # No old backup found, create new subvolume
                        if [ "$DRYRUN" -eq 0 ]; then
-                               btrfs subvolume create \
+                               CreateSubvolume \
                                  "$sys_target" >/dev/null 2>&1; r=$?
                                if [ $r -ne 0 ]; then
-                                       echo "Can't create btrfs subvolume \"$sys_target\", code $r!? \"$system\" skipped!"
+                                       echo "Can't create subvolume \"$sys_target\", code $r!? \"$system\" skipped!"
                                        echo; continue
                                fi
                                echo "Created new subvolume in \"$sys_target\"."
@@ -379,7 +405,7 @@ for f in $sys; do
                                 | cut -d':' -f2- | cut -d. -f1`
                                echo "Removing backup from" $last "..."
                                if [ "$DRYRUN" -eq 0 ]; then
-                                       btrfs subvolume delete \
+                                       DeleteSubvolume \
                                         "$dir" >/dev/null 2>&1
                                        [ $? -eq 0 ] || \
                                         echo "Failed to delete \"$dir\"!"